The Stovebolt Site Forums The Shop Area Engine Shop truck won't start after long drives?

For the past few weeks, my truck has to wait 20-30 minutes before it would start again ONLY after long drives. I assume it's cooling down. I added a heat shield to the ignition coil, but it still has problems. Any suggestions?

Sounds like a similar problem to one I had. I assume It's a 12 volt. Doesn't really matter 6 or 12. Does the coil have a ballast resistor inline?

Tony,

To help find the problem, it is necessary to know HOW the truck won't start when warm.

If it spins fine, but won't start..OR, it barely spins at all!

Each problem has probable causes, and they are quite different.

More info would be required in order to make a wild-educated guess.

Stuart

The engine turns but wont start. (It's kinda like when a battery is going bad.) The engine keeps turning but the more I try the more it seems to loose power.

I'm not sure what a ballast resister is? :S

One more thing... at times, (when I guess it hasn't cooled enough) I pump the gas as I'm turninig the key and the engine struggles to start again and finally does.

Tony,

If your rig is cranking over FINE, but refuses to start when hot, it could be one of several things.

If the carburetor is percolating, or flooding the truck when warm, you will get a fuel odor out the tailpipe, and maybe in the cab.

Immediately after it finally does start, there might be a belch of black some and sputtering of the engine. Next time you drive it, and need to start it warm, try mashing the gas pedal all the way to the floor BEFORE you turn the key. Mash the pedal, hold it mashed for half a minute and then crank the engine to start. See if this makes a difference.

Sometimes heat will influence a coil, increasing its resistance which lowers its ability to give the plugs sufficient zap..this is a possibility.

I don't know what engine you have, but if your valves have not been adjusted in eons, or they have been set too tight, this can cause a hard start when warm.

If the battery is good, and the truck truly does spin over nice and fast, your problems will be either faulty ignition, carburetor issues when hot, or a mechanical fault such as tight valve clearance.

More detective work is required to find out which system is not working properly when warm.

PS..what engine are we talking about?

Stuart

tonys 61 Apache I had the same thing with my 53 and it turned out to be a bunch of small vacum leaks carb base gasket, windseild wiper, and two speed rear end.

Tony,

I just went to the gallery and looked at your rig..nice looking truck! As I recall, this particular setup did tend to heat the starter from the exhaust and cause a slow crank situation.

Your truck would probably have a ballast ignition resistor ounted somewhere on the firewall, or near the distributor. During a START, this is bypassed, and the coil should be getting full battery voltage.

The typical resistor failure would be "Start, but won't run". If you have the funny ceramic looking ballast resistor, you should have either two wires at the + of the coil, or two wires on the coil side of the ballast resistor. You want that full system voltage present to start the truck.

Your latest note above hints at a fuel problem when hot. Your gallery writeup indicates you have a big old four barrel carburetor on the 283.

It could be that your carburetor is leaking, or dripping fuel into the manifold after the engine comes up to temp. Is there a problem between a long trip with the system warm as opposed to a shorter trip with the system warm?

Make sure the choke is operating properly..open fully when warm. By mashing the throttle all the way to the floor, and leaving it there for awhile before starting, you open the primaries all the way and after the fuel evaporates from the initial "mash", you allow maximum air into the rig which sometimes offsets a over-rich fuel situation and gets the engine started.

Too much info..end of novel!


Stuart

Thanks atomarc,
I think I should update my gallery... (that's the touched up photo that was posted)
Also, I have updated the carb to an edelbrok 4bbl manual choke... and I have the CHOKE OPEN all the time.
I forgot to mention this before... not sure if it make a difference.

Could be a vapor lock situation... try putting a clothes pin on the fuel line near the carb.

Could also be a bad condensor.

Tony,

I wonder if the rig had these problems BEFORE the installation of the new carb. I don't generally spread bad press, but the foreman at work installed a Edelbrock Performer (?) carb on his new 350 and had funky hot start problems also.

If you don't have to choke the carburetor when the rig is first started in the morning, it might indicate too much fuel from the git go!

Inkys vapor lock suggestion might be right on the money!

If this is a flooding problem, you should see evidence of it out the tailpipe, or hear the engine blubbering after it does start.

Experiment...next times it does it, either clear the carb the way I described above, OR, pump the hell out of it. It will react to one of these attempts.

Stuart

Guess what, after all this time I finally found out what was wrong. A few months ago I got a new fuel filter & because I didn't want it to bounce & tap the valve cover... I tied the fuel hose (to the carb) to the radiator hose. I guess it WAS heating the fuel line & causing vapor lock?

Thanks all for your help.